[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[compost_tea] nutrients, was Kelp Questions



Dear Dr. E.:

Thanks for your detailed reply.  I'm starting to get a better 
understanding!

If you have good soil biology and apply too much nitrogen via compost or 
other meals, what happens?  If I understand things, this will kill off some 
of your good critters -- probably due to gluttony and then lack of oxygen?

Thanks,
Paulette

-----Original Message-----
From:	soilfoodweb@aol.com [SMTP:soilfoodweb@aol.com]
Sent:	Wednesday, May 07, 2003 11:06 PM
To:	compost_tea@yahoogroups.com
Subject:	Re: [compost_tea] Re:  Kelp Questions

Hi Irene and Paulette -

I didn't see that anyone answered your questions about if you add the kelp, 
rock phosphate or other soil amendments in the tea, do you still need to 
add them to the soil.

Adding the amendments in the tea means you need less of that material than 
you would require in a soil application, because the microbes retain the 
nutrients much better when they are gorwn with the nutrients in the tea. 
When added to soil, nutrients will leach, and be lost from the rooting zone 
without the microorganisms to "grab" them and hold the min the soil.

Of course, roots take up the inorganic nutrients, like nitrate, nitrite, 
ammonium, phosphate, sulfates, potassium, and iron. Typically plants take 
up iron as a chelated form, like ferric citrate, not as elemental iron. The 
microorganisms are key in making certain the nutrients are chelated, and 
thus more plant available.

Since nutrients that are processed by the organisms tend to be more 
available, and are retined better in teh soil, it means you need to add 
less. So, putting the nutrients into the tea gives your plants these 
nutrients.

The reason most N application rates are so high is because you have to 
"fill up" the soil with the nutrients that leached from the soil, because 
there were no organisms to hold the nutrients in the soil. If you stop 
leaching losses, then you don't have to "fill up" the "empty tank" so 
often.

You on'y have to put back the yeild that you take off in plant material. In 
a garden situation, that's only 25 to 35 lbs of N per acre, usually. 
(Assuming you aren't into production mode in your garden. In an ag filed 
the removal in yield tends to run more in the 50 to 75 lab N per acre 
range).

Compost is more than enough N to replace this nutrient need. Compost tea, 
if you use fish hydrolysate, or protein meals, or other organic N source is 
also enough.

But please, don't fall for the NPK game. The N in organic forms is present 
as protein, not as inorganic N, which is the form measured by soils labs 
when they do analyses. Most of the N in soil is not present as nitrate, 
nitrite, ammonium or ammonia. It's present as biology (bacteria, fungi, 
protozoa, nematodes, worms, insect larvae, microarthropods) or as organic 
matter. It is just getting these not-plant available forms converted into 
plant available forms that is important. It is the biology that does that.

So, less is needed, becasue of these considerations. You have to balance 
what was removed in the food you took off last year, but you don't need to 
replace what would have leached, if you don't have the right biology.

Did I confuse you completely? Or is this making sense to you.

If you apply a soil drench of 15 to 20 gal of tea per acre when you plant, 
and then three compost teas at 5 gal per acre on the foliage, and use 0.1% 
each of fish hydrolysate, kelp and some protein source to help fungi, this 
should equate to adding about a pound of N. However ,the efficiency of this 
N for plant growth is likely much greater than inorganic fertilizer N. All 
of the organic N will become available to the plant, given good biology.

Still, in the first few years inot an organic conversion, you will need to 
add compost, fish, or nitrogen-fixing bacteria to add N into the soil in a 
way that will maintain retention in the soil. Compost is the best bet. 
Mulch with a fish, or protein mix would be good too.

How much N is actually in compost? Do not pay attention to the N, P, K that 
people tell you is in compost. Pay attention to the C:N ratio of the 
compost. Good compost is about 15:1 N, which means you are looking at about 
25 lbs of N in 1000 lbs of compost (assuming 50% moisture).

So, you need a ton of compost per acre on your land to meet the N needs of 
your plants. That's barely a dusting of compost over your soil, and in 
fact, is about the same rate of compost as you need to have of inorganic 
fertilizers. But you have to have the biology in the compost to make this 
work.

Can you use fish, protein meals, feathermeal, etc instead? Sure, but 
remember that it has a C:N of perhaps 10:1, and so even less than a ton is 
needed per acre of these materials. Given good biology.


Elaine Ingham
President, Soil Foodweb Inc.
SFI Corvallis, OR
SFI Port Jefferson, NY
SFI Lismore, NSW, Australia
SFI Hilversum, The Netherlands
SFI Cambridge, New Zealand
www.soilfoodweb.com


------------------------ Yahoo! Groups Sponsor ---------------------~-->
Rent DVDs Online - Over 14,500 titles.
No Late Fees & Free Shipping.
Try Netflix for FREE!
http://us.click.yahoo.com/YoVfrB/XP.FAA/uetFAA/0PSxlB/TM
---------------------------------------------------------------------~->

To unsubscribe from this group, send an email to:
compost_tea-unsubscribe@yahoogroups.com

 

Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/